Neonatal jaundice is one of the common symptoms during the neonatal period. It may indicate both normal developmental processes and certain diseases. If it is normal physiological jaundice, there is no need for blood tests. However, if pathological jaundice is suspected, blood tests are generally required. The most common test is a liver function test to determine the level of bilirubin in the blood. Additional tests might be conducted, especially if there is an incompatibility in the blood type between the mother and child. In such cases, tests for the baby's blood type and hemolysis are necessary, along with tests for common infection markers. If the mother had other abnormalities before pregnancy, further blood tests might be warranted based on potential conditions that the baby might exhibit.